Genetics and Reproduction: IVF and ICSI with PGD

Based on Reproductive genetics understanding, therapies are developed and used to maximize outcomes.

Specifically, increased pregnancy rates,decreased incidence of obstetric complications and miscarriage, and the avoidance of fetuses affected by birth defects or other deficiencies are the stated goal of much of the current research in reproductive medicine. The role of genetic testing to guide medical decision making in this regard is sizable and will likely continue to grow in the future.

Genetic evaluations within reproductive medicine may be subdivided into 4 main categories:

1. Preconception genetic testing: The genetic evaluation of prospective parents before pregnancy.

2. Antenatal genetic testing: The genetic evaluation of women who are currently pregnant to determine  the genetic makeup of the developing fetus.

3. Preimplantation genetic testing ( PGD and PGS): The genetic evaluation of an embryo, before uterine transfer, via an embryo biopsy during an in-vitro fertilization (IVF) procedure.

4. Genetic analysis following fetal demise: The genetic evaluation  of the product of conception following a failed pregnancy.

 

Blastocyst transfer may help in repeated IVF failure cases

Recurrent implantation failure may identified after three failed IVF cycles or after transfer of 10 high grade embryos. There are many different factors which may contribute for this recurrent IVF failure, such as parental chromosomal translocations, abnormal uterine anatomy , hydrosalpinx, or inadequate  culture conditions or embryo transfer techniques.

Failure may be due to factors with the “Seed,Soil or the Cultivator”

Some studies have suggested that local injury of the endometrium by means of a catheter or hysteroscopy can induce an inflammatory response that may facilitate the preparation for implantation.

Artificial rupture of the covering of the embryo ( Zona pellucida) may improve implantation: Assisted Hatching, but is still not proved.

Pre-implantation genetic screening of the embryos is now a day used to get and select best embryos. But this strategy did not show any improvement in patient outcome  and did not show any significant difference on clinical pregnancy rates.

A few studies have reported that congenital and acquired prothromotic conditions are more prevalent in women with recurrent implantation failure. Therefore use of low molecular weight heparin (LMWH) and mini dosage of aspirin on patients with thrombophilia and recurrent implantation failure has been discussed, but large studies are required to prove them .

Finally, another possible strategy is to extend embryo culture to blastocyst stage, aiming to improve embryo selection and uterine receptivity

what is my ovarian status, asks one lady after two IVF failure

Mostly , IVF fails due to ” either defect in soil or the seed”, It is very difficult to accept for a couple when we say , that your embryos are not good and we cancel the embryo transfer.

The problem may be in Sperms or in Eggs. But most of the time , if sperm count is good , the eggs are responsible. ( here I should say that, we might also be responsible if our lab conditions are not appropriate, but at our center, we usually do quality control every day, and moreover, if there are two or three cases in one day, and others are appropriate, then we might feel, that we are not at fault).

Most of the time , couple asks a question: What went wrong, why my test is negative, Even they might ask , who is responsible for this failure?

We always do a egg quality  and egg number estimation before commencing the treatment, esp, in little older females.

It is done by Day 2 , transvaginal sonography and a blood test called AMH, that i anti mullerian hormone. It can be done in any day of the menstrual cycle

Incubators in IVF laboratory

Triple gas incubators are usually of three types

  1. It is a bench top warmer and maintains the temperature and you have to feed it with triple gas mix, Mostly 90% N2, 5/6%CO2 and balance air. Here you are dependent on the manufacturer of the triple gas mix, and if it is not supplied properly then you are stuck and there is no incubator in your lab. Secondly, if you want to keep a particular pH in any sequential step, then you can not change the concentration of CO2 at your will or you have to order the separate gas mix. I find it very cumbersome and don’t rely on premix.
  2. Bench top system with inbuilt facility of mixing gas at our will, here we need pure CO2 and N2 feed. It is easy to obtain these cylinders. Here we can fix the CO2 concentration according our pH requirement of the sequential step. We use MIRI multichamber , its performance is good and gas consumption is very less. Fast recovery and we can dedicate each chamber for each patients without disturbing the other. There are other brands too in the market. They are definitely better than simple warmers.
  3. Box type triple gas incubators: These incubators are also with systems of gas mixing at our will. These systems are age old trusted partners of laboratory. Smaller the capacity of incubator, better is recovery and lesser is the consumption of gas. It is better to have a few small box type triple gas incubators , than having a single large incubator ( to accommodate many patients, they consume definitely large amount of gas, esp nitrogen) . We use ASTEC small box type triple gas incubators.

Our policy is : It is important to have a particular pH at different steps, rather believing the CO2 concentration shown on display. We keep CO2 according to the pH requirement, which you can not do with simple warmers.

IVF in previous ectopic cases ( pregnancy in Fallopian tube)

I saw lot of patients with secondary infertility who had ectopic pregnancy after their marriage.

It shows that :

1. They are fertile .

2. The sperms and eggs are usually of good quality.

3. The fertilization site , that  is fallopian tube is at fault.  The tube is patent, ,it allows sperm to go to the egg ,that is waiting at the outer portion of the fallopian tube. The sperm fertilizes the egg, but when the tube pushes the fertilized egg to the uterus , it gets trapped in the tube. It happens because the internal surface of the tube is not smooth. The uterus grows with the growing embryo , but tube can not, so it cracks and the patients land into the severe internal bleeding ( if not seen earlier part of pregnancy). Usually she gets operated and the tube with the pregnancy is removed. Now the lady is with only one tube left.

4. Now she tries for another pregnancy, but couldn’t achieve it. Why? ,as she is fertile, her periods are regular, ,she produces eggs in every month, and staying with her husband, but without pregnancy. This happens because : She had a pregnancy ( ectopic) with the better tube she had ( and it is removed, as she had ectopic). The tube left is usually inferior compared to the tube that is removed, Otherwise she could have a normal pregnancy with this remaining tube.

5. Now the treatment starts , and a Hysteros Salpingo graphy ( HSG) / laparoscopy is done to see the remaining tube , and report comes : patent tubes. Now she is confused . If the remaining tube is patent, then she should have  a natural pregnancy. On that quest : She undergoes lots of useless treatments, like multiple Intra-uterine inseminations (IUI). If her remaining tube is not good , then what ever you do ( with putting sperm in her uterus,IUI) fertilization does not happen.

6. This is because : Tube has to do three functions: a. give passage to sperms and eggs, b. Give nutrition to the fertilized eggs, c. Propel the fertilized egg( embryo) to the uterine cavity. Fault in any of the three function will hamper pregnancy in uterine cavity.

7. So the treatment is not putting sperms in uerine cavity (IUI) , as IUI has not created her earlier ectopic, The treatment is Fertilization. If it is not happening in tube ( in-vivo) , then she should have fertilization,In-vitro ,that is IVF

8. I see many patients with previous ectopic , who waste their time and money in these useless treatments. You can earn money but you can not recover the age. Age makes the eggs poor, and when they come late , the chances of IVF gets poorer. They are increasing their problems and reducing the chances of getting pregnancy because of their own ( ? treating physician’s) ignorance.

9. If they come early for IVF , the chances of success will be more as compared to primary infertility patients ( who never has pregnancy).

10. In India , the tubes are damaged due to Tuberculosis infection(?). some times this inffection damages the uterine lining also ( endometrium).

11. So more delay in getting IVF; May create problem in both ” Seed and the Soil”