Every now and then we see media reports about celebrities in their mid 40s having surprise pregnancies. Or you might hear stories like these from friends or relatives, or see them on TV.

Menopause signals the end of a woman’s reproductive years and happens naturally between age 45 and 55 (the average is 51). After 12 months with no periods, a woman is considered postmenopausal.

While the chance of pregnancy is very low in the years leading up to menopause – the so called menopausal transition or perimenopause – the chance is not zero.

So, what do we know about the chance of conceiving naturally after age 45? And what are the risks?

Is there a spike in fertility before menopause?

The hormonal changes that accompany perimenopause cause changes to the menstrual cycle pattern, and some have suggested there can be a “surge” in fertility at perimenopause. But there’s no evidence this exists.

In the years leading up to menopause, a woman’s periods often become irregular, and she might have some of the common symptoms of menopause such as hot flushes and night sweats.

This might lead women to think they have hit menopause and can’t get pregnant anymore. But while pregnancy in a woman in her mid 40s is significantly less likely compared to a woman in her 20s or 30s, it’s still possible.

The stats for natural pregnancies after age 45

Although women in their mid- to late 40s sometimes have “miracle babies”, the chance of pregnancy is minimal in the five to ten years leading up to menopause.

The monthly chance of pregnancy in a woman aged 30 is about 20%. By age 40 it’s less than 5% and by age 45 the chance is negligible.

We don’t know exactly how many women become pregnant in their mid to late 40s, as many pregnancies at this age miscarry. The risk of miscarriage increases from 10% in women in their 20s to more than 50% in women aged 45 years or older. Also, for personal or medical reasons some pregnancies are terminated.

According to a review of demographic data on age when women had their final birth across several countries, the median age was 38.6 years. But the range of ages reported for last birth in the reviewed studies showed a small proportion of women give birth after age 45.

Having had many children before seems to increase the odds of giving birth after age 45. A study of 209 women in Israel who had conceived spontaneously and given birth after age 45 found 81% had already had six or more deliveries and almost half had had 11 or more previous deliveries.

There’s no reliable data on how common births after age 45 are in Australia. The most recent report on births in Australia show that about 5% of babies are born to women aged 40 years or older.

However, most of those were likely born to women aged between 40 and 45. Also, the data includes women who conceive with assisted reproductive technologies, including with the use of donor eggs. For women in their 40s, using eggs donated by a younger woman significantly increases their chance of having a baby with IVF.

What to be aware of if you experience a late unexpected pregnancy

A surprise pregnancy late in life often comes as a shock and deciding what to do can be difficult.

Depending on their personal circumstances, some women decide to terminate the pregnancy. Contrary to the stereotype that abortions are most common among very young women, women aged 40–44 are more likely to have an abortion than women aged 15–19.

This may in part be explained by the fact older women are up to ten times more likely to have a fetus with chromosomal abnormalities.

There are some extra risks involved in pregnancy when the mother is older. More than half of pregnancies in women aged 45 and older end in miscarriage and some are terminated if prenatal testing shows the fetus has the wrong number of chromosomes.

This is because at that age, most eggs have chromosomal abnormalities. For example, the risk of having a pregnancy affected by Down syndrome is one in 86 at age 40 compared to one in 1,250 at age 20.

Apart from the increased risk of chromosomal abnormalities, advanced maternal age also increases the risk of stillbirth, fetal growth restriction (when the unborn baby doesn’t grow properly), preterm birth, pre-eclampsia, gestational diabetes and caesarean section.

However, it’s important to remember that since the overall risk of all these things is small, even with an increase, the risk is still small and most babies born to older mothers are born healthy.

Multiple births are also more common in older women than in younger women. This is because older women are more likely to release more than one egg if and when they ovulate.

A study of all births in England and Wales found women aged 45 and over were the most likely to have a multiple birth.

The risks of babies being born prematurely and having health complications are higher in twin than singleton pregnancies, and the risks are highest in women of advanced maternal age.

What if you want to become pregnant in your 40s?

If you’re keen to avoid pregnancy during perimenopause, it’s recommended you use contraception.

But if you want to get pregnant in your 40s, there are some things you can do to boost your chance of conceiving and having a healthy baby.

These include preparing for pregnancy by seeing a GP for a preconception health check, taking folic acid and iodine supplements, not smoking, limiting alcohol consumption, maintaining a healthy weight, exercising regularly and having a nutritious diet.

If you get good news, talking to a doctor about what to expect and how to best manage a pregnancy in your 40s can help you be prepared and will allow you to get personalised advice based on your health and circumstances.

Karin Hammarberg, Adjunct Senior Research Fellow, Global and Women’s Health, School of Public Health & Preventive Medicine, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

As we enter a new year armed with resolutions to improve our lives, there’s a good chance we’ll also be carrying something less helpful: extra kilos. At least half a kilogram, to be precise.

“Weight creep” doesn’t have to be inevitable. Here’s what’s behind this sneaky annual occurrence and some practical steps to prevent it.

Small gains add up

Adults tend to gain weight progressively as they age and typically gain an average of 0.5 to 1kg every year.

While this doesn’t seem like much each year, it amounts to 5kg over a decade. The slow-but-steady nature of weight creep is why many of us won’t notice the extra weight gained until we’re in our fifties.

Why do we gain weight?

Subtle, gradual lifestyle shifts as we progress through life and age-related biological changes cause us to gain weight. Our:

• activity levels decline. Longer work hours and family commitments can see us become more sedentary and have less time for exercise, which means we burn fewer calories
• diets worsen. With frenetic work and family schedules, we sometimes turn to pre-packaged and fast foods. These processed and discretionary foods are loaded with hidden sugars, salts and unhealthy fats. A better financial position later in life can also result in more dining out, which is associated with a higher total energy intake
• sleep decreases. Busy lives and screen use can mean we don’t get enough sleep. This disturbs our body’s energy balance, increasing our feelings of hunger, triggering cravings and decreasing our energy

• stress increases. Financial, relationship and work-related stress increases our body’s production of cortisol, triggering food cravings and promoting fat storage
• metabolism slows. Around the age of 40, our muscle mass naturally declines, and our body fat starts increasing. Muscle mass helps determine our metabolic rate, so when our muscle mass decreases, our bodies start to burn fewer calories at rest.

We also tend to gain a small amount of weight during festive periods – times filled with calorie-rich foods and drinks, when exercise and sleep are often overlooked. One study of Australian adults found participants gained 0.5 kilograms on average over the Christmas/New Year period and an average of 0.25 kilograms around Easter.

Why we need to prevent weight creep

It’s important to prevent weight creep for two key reasons:

1. Weight creep resets our body’s set point

Set-point theory suggests we each have a predetermined weight or set point. Our body works to keep our weight around this set point, adjusting our biological systems to regulate how much we eat, how we store fat and expend energy.

When we gain weight, our set point resets to the new, higher weight. Our body adapts to protect this new weight, making it challenging to lose the weight we’ve gained.

But it’s also possible to lower your set point if you lose weight gradually and with an interval weight loss approach. Specifically, losing weight in small manageable chunks you can sustain – periods of weight loss, followed by periods of weight maintenance, and so on, until you achieve your goal weight.

2. Weight creep can lead to obesity and health issues

Undetected and unmanaged weight creep can result in obesity which can increase our risk of heart disease, strokes, type 2 diabetes, osteoporosis and several types of cancers (including breast, colorectal, oesophageal, kidney, gallbladder, uterine, pancreatic and liver).

A large study examined the link between weight gain from early to middle adulthood and health outcomes later in life, following people for around 15 years. It found those who gained 2.5 to 10kg over this period had an increased incidence of type 2 diabetes, heart disease, strokes, obesity-related cancer and death compared to participants who had maintained a stable weight.

Fortunately, there are steps we can take to build lasting habits that will make weight creep a thing of the past.

7 practical steps to prevent weight creep

1. Eat from big to small

Aim to consume most of your food earlier in the day and taper your meal sizes to ensure dinner is the smallest meal you eat.

A low-calorie or small breakfast leads to increased feelings of hunger, specifically appetite for sweets, across the course of the day.

We burn the calories from a meal 2.5 times more efficiently in the morning than in the evening. So emphasising breakfast over dinner is also good for weight management.

2. Use chopsticks, a teaspoon or an oyster fork

Sit at the table for dinner and use different utensils to encourage eating more slowly.

This gives your brain time to recognise and adapt to signals from your stomach telling you you’re full.

3. Eat the full rainbow

Fill your plate with vegetables and fruits of different colours first to support eating a high-fibre, nutrient-dense diet that will keep you feeling full and satisfied.

Meals also need to be balanced and include a source of protein, wholegrain carbohydrates and healthy fat to meet our dietary needs – for example, eggs on wholegrain toast with avocado.

4. Reach for nature first

Retrain your brain to rely on nature’s treats – fresh vegetables, fruit, honey, nuts and seeds. In their natural state, these foods release the same pleasure response in the brain as ultra-processed and fast foods, helping you avoid unnecessary calories, sugar, salt and unhealthy fats.

5. Choose to move

Look for ways to incorporate incidental activity into your daily routine – such as taking the stairs instead of the lift – and boost your exercise by challenging yourself to try a new activity.

Just be sure to include variety, as doing the same activities every day often results in boredom and avoidance.

6. Prioritise sleep

Set yourself a goal of getting a minimum of seven hours of uninterrupted sleep each night, and help yourself achieve it by avoiding screens for an hour or two before bed.

7. Weigh yourself regularly

Getting into the habit of weighing yourself weekly is a guaranteed way to help avoid the kilos creeping up on us. Aim to weigh yourself on the same day, at the same time and in the same environment each week and use the best quality scales you can afford.

At the Boden Group, Charles Perkins Centre, we are studying the science of obesity and running clinical trials for weight loss. You can register here to express your interest.

Nick Fuller, Clinical Trials Director, Department of Endocrinology, RPA Hospital, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.