What Is Multiple Ovulation? Definition & Causes

By (gynecologist), (embryologist) and (invitra staff).
Last Update: 03/02/2020

Some women may release more than one egg in a menstrual cycle, i.e., have several ovulations in the same month. In addition, all of these eggs are susceptible to fertilization during this menstrual cycle, which would explain the births of twins.

The origin of multiple ovulation is due to several causes, which are grouped into two types: hereditary and acquired. In fertility treatments such as artificial insemination (AI), a woman may develop and ovulate more than one egg as a result of ovarian stimulation.

What is multiple ovulation?

Normally, at the beginning of the menstrual cycle there is an increase in follicle stimulating hormone (FSH) that causes the development of various ovarian follicles. Only one of these follicles will predominate and reach the final stage of maturity. At this time, the predominant follicle will release an egg by the action of luteinizing hormone (LH), known as the ovulation phase.

However, some women may have several ovulations in the same menstrual cycle. This means that more than one predominant follicle will develop and, therefore, several eggs (usually two) will be released in one month. This phenomenon is called multiple ovulation.

The result of two ovulations in the same menstrual cycle of the woman is the reason for the birth of non-identical twins. In these situations, the two released eggs are fertilized by two different sperm, called superfertilization.

Causes of multiple ovulation

Fundamentally, there are two main causes of multiple ovulations:

  • Hereditary causes: due to the inheritance of genes whose expression favors multiple ovulation. These are genes that intervene in the regulation of follicles and/or in the increase of progesterone levels.
  • Acquired causes: as a consequence of overweight, advanced age, ovarian stimulation in assisted reproduction treatments or the use of hormonal contraceptives, there may be a greater risk of multiple ovulation in women.

Symptoms

In principle, there are no differences in the symptomatology of women with multiple ovulation compared to women with normal ovulation.

Some symptoms during ovulation that women describe are as follows:

  • Pain in the lower belly area
  • Changes in body temperature
  • Increased amount and texture of vaginal discharge.
  • Alterations in the cervix.
  • Gas and abdominal swelling.
  • Muscle pain.
  • Bone pain.

It should be noted that every woman is different and some women do not suffer any change in their body during ovulation.

Multiple ovulation and pregnancy

Women who have multiple ovulation have a greater risk that both released eggs will be fertilized by two sperm. When this multiple egg fertilization occurs, the result will be a pregnancy of two non-identical babies or twins.

Assisted reproduction treatments

In order to achieve gestation through assisted reproduction techniques, it is necessary to follow several stages and one of them is ovarian stimulation in women through the administration of drugs. In this way, the growth of several ovarian follicles is guaranteed.

Therefore, ovarian stimulation in artificial insemination (AI) or timed intercourse makes 1-2 eggs available for fertilization. In this type of technique, multiple pregnancies occur when the woman is stimulated with high doses of hormones or for more than a few days and, therefore, there is greater development of eggs.

On the other hand, the objective of ovarian stimulation in in vitro fertilization (IVF) is to obtain various eggs that will be fertilized in the laboratory to obtain embryos. Therefore, the woman is given higher hormonal doses than for AI. In these cases, the reason that there is a higher percentage of multiple pregnancy is because most people decide to transfer two embryos generated by IVF to increase the chance that at least one of them will implant in the uterus.

For more information on multiple pregnancy, read on in the following article: Multiple pregnancies in assisted reproduction: pros and cons.

FAQs from users

How common are spontaneous multiple ovulations?

By Dra. Lydia Pilar Suárez (gynecologist).

Natural double ovulation is studied by the rate of spontaneous twin pregnancies that occurs in 1 out of 80 pregnancies.

In Spain the incidence of multiple ovulation in women is approximately 1.25%. However, there are countries, such as Nigeria, where the incidence is higher and others, such as Japan, where it is lower.

How can multiple ovulation be detected?

By Marta Barranquero Gómez (embryologist).

The only way to detect multiple ovulation is through an ultrasound test, that is, through an ultrasound scan in which the presence of two luteal bodies in the ovaries will be seen.

Can you ovulate twice in the same month?

By Marta Barranquero Gómez (embryologist).

Yes, although it is rare for two ovulations to occur. Sometimes, some women may release two or three eggs in a single menstrual cycle, which would explain the birth of twins.

Can Omifin produce multiple ovulation?

By Marta Barranquero Gómez (embryologist).

Yes. Omifin is a drug used for ovarian stimulation. Therefore, the function of this drug is to increase the production of mature eggs, improving fertility and the chances of achieving a pregnancy.

However, it should be remembered that when a large number of eggs are generated, there is a greater risk of multiple pregnancy.

Suggested for you

Want to know in more detail how the menstrual cycle works? Read on in the following article: The different phases of the menstrual cylce.

We have also commented that assisted reproduction treatments are responsible for numerous multiple pregnancies, but can have risks for the woman and the baby. More information here: Multiple Pregnancy Risks for Mother and Babies.

Our editors have made great efforts to create this content for you. By sharing this post, you are helping us to keep ourselves motivated to work even harder.

References

Hummel, T., Gollisch, R., Wildt, G., and Kobal, G. (1991). Changes in olfactory perception during the menstrual cycle. Experentia, 47, 712-715.

Qi MY, Xu LQ, Zhang JN, Li MO, Lu MH, Yao YC. Effect of the Booroola fecundity (FecB) gene on the reproductive performance of ewes under assisted reproduction. Theriogenology. 2019 Nov 1. pii: S0093-691X(19)30492-3. doi: 10.1016/j.

Roser JF, Etcharren MV, Miragaya MH, Mutto A, Colgin M, Losinno L, Ross PJ. Superovulation, embryo recovery, and pregnancy rates from seasonally anovulatory donor mares treated with recombinant equine FSH (reFSH). Theriogenology. 2019 Oct 29. pii: S0093-691X(19)30484-4. doi: 10.1016/j

Thomas S, Sebastian T, Karthikeyan M, Mangalaraj AM, Aleyamma TK, Kamath MS. Effectiveness of spontaneous ovulation as monitored by urinary luteinising hormone versus induced ovulation by administration of human chorionic gonadotrophin in couples undergoing gonadotrophin-stimulated intrauterine insemination: a randomised controlled trial.BJOG. 2019 Aug;126 Suppl 4:58-65. doi: 10.1111/1471-0528.15830.

Wilcox AJ, Weinberg CR, Baird DB. Timing of intercourse in relation to ovulation: effects on the probability of conception, survival of the pregnancy and sex of the baby. N Engl J Med 1995;333:1517– 1521.

FAQs from users: 'How common are spontaneous multiple ovulations?', 'How can multiple ovulation be detected?', 'Can you ovulate twice in the same month?' and 'Can Omifin produce multiple ovulation?'.

Read more

Authors and contributors

Dra. Lydia Pilar Suárez
Dra. Lydia Pilar Suárez
Gynecologist
Bachelor degree in Medicine and Surgery at the Universidad de Oviedo in Asturias. Specialization in Obstetrics and Gynecology at the University Hospital of San Carlos de Madrid. Master in Assisted Reproduction at the University of Rey Juan Carlos in collaboration with the Valencian Fertility Clinic IVI. More information about Dra. Lydia Pilar Suárez
Licence number: 64136
 Marta Barranquero Gómez
Marta Barranquero Gómez
Embryologist
Graduated in Biochemistry and Biomedical Sciences by the University of Valencia (UV) and specialized in Assisted Reproduction by the University of Alcalá de Henares (UAH) in collaboration with Ginefiv and in Clinical Genetics by the University of Alcalá de Henares (UAH). More information about Marta Barranquero Gómez
Adapted into english by:
 Romina Packan
Romina Packan
inviTRA Staff
Editor and translator for the English and German edition of inviTRA. More information about Romina Packan

Find the latest news on assisted reproduction in our channels.