In Croatia, egg donation is allowed as long as it involves a woman who is unable to use her own eggs or to avoid the transmission of a severe hereditary condition from the mother. Thus, a woman can turn to donor eggs in cases as the following:
- Poor ovarian reserve
- The woman has run out of her supply of eggs
- Premature ovarian failure (POF) or early menopause
- Likelihood of passing a severe genetic disease to offspring
- Advanced maternal age
- Recurrent pregnancy loss (RPL)
The above listed are the most common reasons why a woman may be unable to contribute her own genetic material, being advanced maternal age the most usual one. Over time, a woman’s supply of eggs, along with egg quality, keeps on diminishing, which translates into fewer chances of getting pregnant via in vitro fertilization (IVF) with own ova.
Bearing this in mind, we can say that, for a number of women, in vitro fertilization with donor eggs may turn out to be their chance to become mothers. The embryos obtained are usually of high quality, and therefore normally have a great implantation potential.
Only heterosexual couples are permitted to access fertility treatments, including egg donation, within Croatia.
The regulations governing egg donation and assisted reproductive technology (ART) in this country are gathered in the Medically Assisted Procreation Act, Official Gazette of the Republic of Croatia, No. 86/12. In accordance with it, egg donors must act altruistically and voluntarily.
Donor oocytes can have been donated by two different types of donors:
- Women who willingly donate eggs, not undergoing their own IVF protocol.
- Women who are already on an IVF cycle and decide to donate some of their excess eggs—an option known as oocyte sharing.
In both cases, children born using donor oocytes have the right to know their genetic origins once they turn 18 years old. This implies they can have a access to identifiable data on their egg donor, and therefore to know about her identity.
Under no circumstances can the identity of the donor be disclosed to the intended parents. They can only obtain non-identifying information about the donor if the donor-conceived child develops a serious health problem, but even in this case, the donor’s identity would remain unrevealed.
On the other hand, neither the egg donor is allowed to get identifiable information on the receiving couple, nor about the donor-conceived individual. Such piece of information is confidential above all.
Each oocyte donor can have a maximum of 3 children born from her gamete donations. Once this limit number is reached, the excess donated eggs are destroyed.
Egg donation procedure
Whenever donor eggs are to be used, the ART of choice is in vitro fertilization, as donor eggs have to necessarily be fertilized in the laboratory. Fertilization can be done through conventional IVF or via ICSI, depending on how good is the husband’s semen sample.
In case the donor contributes her eggs but she is not undergoing her own IVF program, her menstrual cycle would be stimulated in order to trigger the production of a greater number of mature oocytes. They would be later harvested via follicular puncture.
To that end, donors have to administer hormonal medications which are applied intravenously. During the ovulation induction process, follicle growth inside their ovaries is monitored to see how they are developing. When the eggs are mature enough, a date for egg retrieval is set, and the oocytes are retrieved from ovaries by suction (needle aspiration).
The donor’s cycle can be synchronized with that of the recipient, in which case it would be a fresh donor cycle. Thus, it would involve stimulating the ovaries of the donor, while at the same time the recipient’s endometrium is caused to thicken, as it would happen in a natural cycle.
However, in the case of frozen donor cycles, as in the case of oocyte sharing, the only previous step involves preparing the recipient’s endometrium.
For the endometrium to be well prepared, administering gonadotropins and progesterone is required. This step also needs to be regularly monitored to see the pattern of growth of endometrial thickness, which have to reach around 7-10 mm.