Ovarian Hyper-stimulation Syndrome is a condition that can happen as a side-effect of fertility medications. Previously when only 'long protocol' was available OHSS was relatively common (almost 5-10% of all cycles) but now with the newer, safer 'Antagonist' protocol OHSS is very rarely seen. Still, OHSS remains as one of the commonly known terms in IVF treatment and we get queries from patients asking about OHSS commonly.

What is OHSS?

OHSS or Ovarian Hyper-stimulation Syndrome is a medical condition of enlarged ovaries, fluid accumulation in third space regions and hemoconcentration occurring due to elevated Estrogen levels during Controlled Ovarian Stimulation as a part of IVF or ICSI treatment. In simple terms OHSS is the unintentional excessive stimulation of the ovaries leading to unpleasant side-effects that happens very rarely nowadays due to the advent of innovative Controlled Ovarian Stimulation protocols.

OHSS is classified into mild, moderate and severe degrees depending on ovarian size, Hemotocrit, presence of thrombosis, ascites and urine output. With the advent of newer 'trigger' injections like GnRH agonists and low-dose HCG, severe OHSS is almost never seen. Indeed, at Janini IVF, the best IVF centre in Delhi NCR, we assure you that our tailor made individualised stimulation protocols would ensure that our patients do not have to suffer from the consequences of OHSS. Dr. Dalal with his extensive experience in more than 10,000 IVF cycles, with competent staff trained in stimulation protocols, is instrumental in making Janini IVF as 'OHSS FREE CLINIC'.

Timing when OHSS develops

OHSS occurs after a few days of egg retrieval procedure. OHSS can be 'Early' when it happens on the day or after a few days of egg retrieval; or 'Late' when it happens much after the embryo transfer. The 'Late' OHSS is not due to Ovarian Stimulation but happens due to a developing pregnancy. Yes, pregnancy can rarely cause OHSS. The reason being the developing pregnancy has cells called "trophoblasts" that secrete a hormone called beta-HCG which plays a key role in the pathogenesis of OHSS. This late OHSS subsides in a few weeks and if it is severe there is no option but to terminate the pregnancy. Thankfully, late OHSS is hardly that severe.

Symptoms of OHSS

• Ovaries get swollen from normal almond sized to lemon or even orange sized. This leads to lower abdominal aches and pains.
• Nausea and vomiting
• Constipation is common. Rarely loose motions can also happen.
• If ascites (fluid accumulation in abdomen) present can cause tenderness to touch
• Severe OHSS which is very rare nowadays has symptoms like decreased urine output, severe pain, uneasiness, breathing troubles, sudden weight gain and dizziness.
• Severe OHSS is rarely seen and indeed Janini IVF takes pride in being one of the few 'OHSS free' clinics of the country. We achieve this feat by individualised treatment protocols and safer stimulation injections used during the IVF cycle.

Compared to severe OHSS which is virtually eliminated mild OHSS can happen in about 5-10% of patients undergoing IVF treatment. This is an innocuous condition and we will prescribe you pain killers and laxatives. You should drink lots of water and be mobile. The symptoms will abate in a few days and you will be back to normal soon.

Cause of OHSS

The key hormone responsible for causing OHSS is HCG which is given to 'trigger' ovulation when the follicles are mature. High dose of circulating HCG causes production of cytokines and growth factors that bring about a cascade of events leading to OHSS. Good news is today there are stimulation protocols that completely avoid the use of HCG. We have an injection called GnRH agonist that can replace HCG for the final trigger and this would essentially eliminate OHSS from developing.

Prevention of early OHSS can be Primordial, Primary, Secondary and Tertiary. Primordial prevention is looking for patient profile that would tell us a particular patient is predisposed to develop OHSS so that we use alternative stimulation protocols. Primary prevention is using low dose FSH in a titrated dose. Secondary prevention is GnRH agonist trigger, coasting and freezing all embryos. Tertiary prevention is cancellation of cycle and is hardly required these days.

Late OHSS, on the other hand, happens due to the developing pregnancy and cannot be prevented that easily. Transferring embryos in a frozen cycle instead of a fresh cycle prevents late OHSS from occurring. However once late OHSS develops, the management is essentially symptomatic and usually late OHSS abates with time.

How common is OHSS?

According to published medical literature the following incidence rates are reported for OHSS:-

• Mild OHSS - 10-25% of cycles. Mild OHSS can be considered as a 'normal' response to ovarian stimulation and there is nothing to worry about if it happens. There is very low chance of it progressing to severe OHSS.
• Moderate OHSS happens in 2-5% cases
• Severe OHSS is reported in 0.1-2% of all cycles in published papers.

Again, the incidence of OHSS has dropped drastically after the usage of the newer and safer Ovarian Stimulation protocols and the rates mentioned above are nothing but an over-estimate.

Risk factors for developing OHSS

There are certain conditions that increase your chances of developing OHSS and it is important that during history taking and counselling sessions at Janini IVF, providing the best you let us know if you have any of them. Some of those conditions are :-

• PCOS patients - PCOS patients typically have a lot of follicles that fail to develop into mature eggs. During ovarian stimulation unfortunately all of them grow to large sizes leading to OHSS.
• Those with previous history of OHSS - let us know if you availed IVF elsewhere and developed OHSS - we would use special individualised treatment protocols in your case to prevent OHSS.
• Very high AMH levels (above 6 or so)
• Lean and thin patients with high Antral follicle count
• Very high Estradiol (E2) levels while receiving stimulation

Why Janini IVF centre?

Armed with over 10,000 IVF/ICSI cycles of experience and highly advanced technology, we at Janini IVF, the best oocyte donation treatment in Delhi, incorporate safe, individualised and patient-specific treatment protocols that are best suited to each individual's needs. A detailed history taking and evaluation of your case will help us know about your risks of developing OHSS and if you are in the high risk category we would use alternative Ovarian Stimulation protocols to ensure you would not develop OHSS. At Janini IVF, our highly advanced lab equipment and qualified in-house embryology team ensures highest success rates with minimal complications. We are truly an OHSS-free clinic.