Skip to main content

When you are trying to conceive, the possibility of giving birth to twins or triplets or even more babies from a single pregnancy is a potential reality. 

Fertility treatments that boost ovulation can lead to twins, triplets, or higher order multiples. In fact, conceiving multiples is a possible risk of fertility treatments, but this can be decreased with careful monitoring and single embryo transfer (for IVF treatment) if possible.

There are positive benefits to having multiples, so you may be wondering why conceiving multiples is considered a risk and not a possible benefit to fertility treatments. If you’ve been struggling to get pregnant, wouldn’t a double or triple blessing be a good thing?

Of course, it would.  But the point is that multiple pregnancies come with risks to you and your babies. The primary goal of fertility treatment is for you to conceive and give birth to one healthy baby at a time.

There are a number of factors that contribute to the likelihood of birthing twins and other multiples. For instance, when you are on certain fertility treatments that require the use of ovulation drugs, they tend to make it more likely that you’ll conceive multiples. However, your height, age, and even family history can increase your odds of birthing more than one.

If you are over 30, you are more likely to conceive twins because your hormonal follicle stimulating hormone (FSH) level rises as you get older. The FSH is responsible for the development of your eggs in the ovaries before being released.

A family history of identical twins does not necessarily make it more likely you’ll have multiples, although the children of male identical twins may be more likely to have their own identical twins.

However, if you have fraternal twins (non-identical) in your family, your chances of conceiving twins is more likely. If there are fraternal twins on both your side and on the side of your spouse, your odds for twins goes up even higher.

Weight is another important factor in determining whether or not multiples are conceived. If you are obese, with a body mass index (BMI) over 30, you are more likely to conceive twins than if you had a healthier BMI.

This is another ironic situation since overweight women are also more likely to have difficulty conceiving. The explanation here is that extra fat leads to increased levels of estrogen and the higher levels of estrogen can lead to overstimulation of the ovaries. Instead of releasing just one egg at ovulation, the ovaries may release two or more.

If you are taller than average, you are more likely to have twins. Why this happens isn’t really clear, but one theory is that better nutrition, which may lead to more height, is partially behind the increased rate of twins.

It has long been known that women who conceive while breastfeeding are more likely to conceive twins than women who are not breastfeeding. Although breastfeeding can suppress fertility and prevent pregnancy, specifically during a baby’s first six months if the baby is exclusively breastfed, however, it is possible to get pregnant when breastfeeding, and with twins.

Research is still ongoing, but some studies have found that women who eat a lot of dairy products are more likely to conceive twins. One theory is that the growth hormones given to cows affect the hormone levels in humans.

Not all treatments for infertility increase your odds of twins and other multiples, but most do. For instance, treatment with fertility drugs like Clomid does. Gonadotropins (also known as injectables), IUI treatment, when used along with fertility drugs can also produce multiple births. 

Essentially IVF treatment is commonly associated with multiple birth, often twin pregnancies, but they could also be triplet or higher order pregnancies.

Contrary to popular belief, IVF treatment is not the main source of triplet and higher order pregnancies, however IVF twins are relatively common, with the twin rate highest for women younger than 35, The IVF twin rate is lower for women over age 35 likely due to the overall decreased success rate as a woman ages.

The rate of multiple births appears to have peaked and has been gradually declining over the past decade because fertility treatment policies are adopting transfer of fewer embryos to minimize the risks of multiple pregnancy. 

In the general population, identical twin pregnancies are not very common. But while most multiple pregnancies conceived with fertility treatments are fraternal twins, the use of fertility treatment does increase your risk of having identical twins.

Your chances of having multiple births will depend not just on your use of fertility drugs, but also your family history, race, age, and many other factors. All these factors do work together. 

Your chances of conceiving multiples will also be affected by your particular cause of infertility. If you are a young woman with healthy eggs, you are more likely to conceive twins or triplets or even higher order births than a woman that is over 40, and whose egg quality is poor.

The twin and multiple rates also vary from fertility clinic to clinic. Twin rates differ based on how carefully ovulation stimulation is tracked during fertility drug use and how many embryos are transferred during IVF.

The bottom line is that while having multiple babies at the same time may sound like an attractive proposition for you after your struggle with infertility, it really is best to aim for one healthy baby.

Your odds of having multiples can be controlled with careful monitoring and single-embryo transfer during IVF.

In the event that you do conceive twins or more, it is important to appreciate that good prenatal care can reduce your risk of complications. 

Leave a Reply