Multiple pregnancies, where a woman is pregnant with more than one baby at the same time, are relatively rare but have been increasing in recent years due to advances in fertility treatments and other factors.
Understanding what causes multiple pregnancies can help prospective parents and healthcare providers anticipate and manage this unique pregnancy.
1. Heredity
A family history of multiple pregnancies, especially on the mother’s side, increases the likelihood of having multiples. This genetic predisposition is more strongly linked to fraternal twins, where more than one egg is released and fertilized.
2. Older Maternal Age
Women over the age of 30, particularly those between 35 to 40, are more likely to have multiple pregnancies. This is because hormonal changes with age can lead to the release of more than one egg during ovulation.
3. High Parity
Women who have had several previous pregnancies are at higher risk of multiple pregnancies in subsequent pregnancies. This increased chance is partly due to changes in hormonal patterns and ovarian function after multiple pregnancies.
4. Race
Race can play a role in multiple pregnancies. For example, African-American women have a higher incidence of twins compared to Asian or Native American women who have lower rates. White women, especially those over 35, tend to have higher rates of higher-order multiples (triplets or more).
Other Factors
- Fertility treatments such as ovulation-inducing medications and assisted reproductive technologies (ART), like IVF, significantly increase the risk of multiples because they often involve releasing or implanting multiple eggs/embryos.
- Lifestyle factors such as height and body weight can also influence the likelihood of multiple births.
Conclusion
Multiple pregnancies result from a combination of genetic, hormonal, demographic, and medical factors. With the rise in fertility treatments, the incidence of multiples has increased. Early recognition and careful medical management are essential to ensure the health and safety of both mothers and babies in multiple pregnancies.