What Causes Multiple Births?
The news is full of stories of women having up six or more babies at once; these news reports often focus on the fact that these women have undergone fertility treatments, and their extreme multiple births are a direct result of these treatments. However, some women experience multiple births without undergoing fertility treatments, and this phenomenon seems to be on the rise.
Multiple births are defined as any birth of more than one fetus that occurs in a single pregnancy. Most multiple births that naturally occur to parents are seen as two or three babies in one pregnancy. Twins and triplets have never been common, but they occur much more frequently in nature than higher order multiple births. Multiple births that naturally occur happen in one of two ways. The first cause of multiple births occurs when a women releases multiple eggs during her time of ovulation instead of just normally one; all of these eggs can be fertilized through one incidence of intercourse. The second cause of multiple births occurs when a women ovulates one egg, but the fertilized egg splits into two; these results in identical twins.
There are always variations to multiple birth causes. For example, a woman releases two eggs during her ovulation. Both eggs are fertilized but one of the fertilized eggs splits; the woman is then pregnant with triplets. Or, a woman releases two eggs and both eggs are fertilized and they both split; the woman is then pregnant with quadruplets.
Multiple births have been increasing in the last decade, and much of that increase has been attributed to fertility treatments. During these treatments a women may be given artificial hormones that stimulate the release of an unusual amount of eggs during one ovulation cycle; sometimes up to 20 eggs can be released from these treatments.
The eggs can be collected, fertilized, and then placed in the mother’s uterus. Not all the embryos may develop, and some mothers to be have multiple embryos placed in her embryo to ensure a pregnancy occurs; she may then be surprised to find that she is pregnant with 5, 6, or even 7 embryos.
The increasing rates of multiple births are not all attributed to modern fertility treatments. In an effort to understand why natural multiple births are slowly increasing, scientist discovered that the age and nutrition of the mother can contribute to multiple births. Interestingly enough, women over 35 have an increased change of having a multiple birth. As more women are waiting until later in life to have children, we are seeing a slight increase in multiple births. Increased nutrition in our diets has also been determined to be a result of increased multiple births.
Whatever the cause of increased multiple births, these births do carry their own increased risks and cautions. Both the mother and the fetuses need extra care and support during multiple birth pregnancies. Multiple births cannot be taken lightly, and the new moms and dads to be will need to be extra prepared to handle the rigors of their newly increased family.