Pregnancy loss after a positive IVF

In today’s post we try to explain the causes of natural miscarriage, especially after In Vitro Fertilisation (IVF).

Miscarriage is defined as the spontaneous interruption of pregnancy before reaching foetal viability, that is, before 22 weeks of gestation, or the expulsion or extraction of a foetus weighing 500g or less.

Human reproduction is extremely inefficient compared with other mammalian species. Between 50 – 70% of spontaneous pregnancies are lost in the first weeks of gestation. Most of these go unnoticed, especially if they occur around the time of an expected period. Only 40% of these losses are detected through a urine pregnancy test.

How can the risk of miscarriage after IVF be reduced?

We know that overcoming a miscarriage is not easy and that is why at Fertility Madrid we work to ensure the highest rate of healthy babies and newborns. Below, we explain the two most effective ways to reduce the apparent risk of miscarriage after IVF.

• One approach is to analyse the genetic information of the foetus, as well as that of either partner if they present any genetic anomaly or a family history of this type. This is done through preimplantation genetic testing (PGT).

• Another way to help reduce the risk of miscarriage after IVF is to identify any medical cause considered “recurrent” in relation to miscarriage. When the risk assessed is severe, the patient may be advised to undergo another assisted reproduction treatment that, in their case, offers greater safety.

Possible causes of miscarriage after IVF treatment

The miscarriage rate decreases significantly as pregnancy progresses, being lower than 3% after 11 weeks.

Among the causes of miscarriage in pregnancies conceived naturally or through assisted reproduction techniques such as in vitro fertilisation (IVF), genetic causes account for 60% of early pregnancy losses. For this reason, the rate of losses also increases with maternal age.

Other causes of miscarriage include endocrinological diseases, anatomical defects of the female genital tract, infections, immune factors, chemical agents, hereditary metabolic diseases, trauma, or maternal illnesses, among others.

Miscarriage is a very common event in human reproduction; however, it is recommended to carry out tests to look for a potentially treatable underlying cause after 3 consecutive (or non-consecutive) miscarriages, and in women over 35 years of age or with infertility after 2 miscarriages.

Evolution of the miscarriage rate according to maternal age

• Women under 35 years have a 15% probability of miscarriage.

• Women aged 35–39 years have a 25% probability of miscarriage.

• Women aged 40–44 years have a 51% probability of miscarriage.

• Women over 45 years have a 93.4% probability of miscarriage.

Do you have any questions or need more information?

At Fertility Madrid, we are specialists in treatments such as egg donation, in vitro fertilisation (IVF), and artificial insemination, among others.
Do not hesitate to contact our professionals at our fertility clinic — they will be happy to answer all your questions with no obligation.