Common practices of high-performing IVF clinics (2016-2017)

Researchers in a 2022 study revealed that high-performing IVF clinics in the US commonly practice freezing blastocysts, controlling air quality, using intramuscular progesterone for FETs, culturing embryos under low oxygen, and more.

Ten years ago, Van Voorhis et al. (2010) identified common practices among 10 different high-performing IVF clinics. Some of these practices included:

• Testing all patients for ovarian reserve and endometrial defects
• Combined LH and FSH stimulation
• Ultrasound guidance for embryo transfers
• ICSI where appropriate
• Group culture of embryos
• Use of blastocysts
• Good air quality
• Heated stages for manipulation of eggs/embryos

A lot can change in 10 years! So Knudtson et al. (2022) wanted to provide an update.

In their report, high-performance IVF centers were identified by having the highest cumulative singleton live birth rates. They looked at women <37 years old between 2016 and 2017. A total of 13 clinics were included anonymously and asked to complete a survey that asked about:

• IVF statistics
• Personnel
• Medical practice (age restrictions, supplements, ovarian stimulaton, etc.)
• IVF lab practices (PGT-A, mosaic embryos, semen analysis, equipment, etc.)

Let’s take a look at each of these categories and see what these clinics have in common!

---

IVF statistics

On average, each center performed about 1500 cycles (including fresh and frozen cycles).

For cycles in 2016, the cumulative rate of a singleton live birth was 59% for women <35 and 47% for women 35-37 years old. Cumulative in this report means that these cycles started in 2016 and patients had that year to transfer embryos fresh/frozen until they achieved a live birth.

For cycles in 2017, the cumulative rate of a singleton live birth was 61% for women <35 and 50% for women 35-37.

5 of the 13 clinics were from academic centers, and 6 of the clinics had been operating for 21 years or more.

Staff

Staffing is important to prevent errors or burnout! Here they looked at the different kinds of staff and how many there were for a certain number of egg retrievals or total cycles (which included fresh + frozen cycles). You can use sart.org to find your clinic and see how many cycles they performed in previous years. Just remember that “total cycles” includes fresh and frozen cycles.

• 1 physician per 123 egg retrievals, or 1 physician per 259 total cycles
• 1 registered nurse per 83 egg retrievals, or 1 per 145 total cycles
• 1 embryologist per 152 egg retrievals, or 1 per 273 total cycles

Additionally, many clinics had medical assistants (12/13), sonographers (7/13), andrologists (12/13), financial counselors (12/13), and psychological support (6/13). Most clinics (11/13) also had an on-site laboratory director.

Clinical practices

Age restrictions:

• Ten of the 13 clinics had age restrictions (with an age limit that ranged from 44 to 50 years).

BMI restrictions:

• Twelve of the 13 clinics had BMI restrictions (that ranged from 40 to 50).

Supplements:

• DOR patients were encouraged to use CoQ10 and acupuncture, but not metformin, aspirin and testosterone.
• Half the clinics used DHEA and growth hormone.

Ovarian stimulation:

• Twelve clinics used birth control in most cycles.
• All clinics used a combination of FSH and LH but the dose varied.

Male testing:

• All centers required a semen analysis before IVF.
• None measured DNA fragmentation or antisperm antibodies.

Progesterone:

• Ten clinics measured progesterone during stimulation.
• Fresh transfers were discouraged if progesterone was >1.5 – 2.0 ng/ml.

Embryo transfers.

• Ten clinics did fresh embryo transfers, 3 did only frozen transfers.
• Minimum endometrial thickness for frozen transfers varied from 6-8 mm, with 2 clinics having no minimum.
• All used intramuscular progesterone, often beginning it 120-131 hours pre-transfer.
• ERA was rarely used.
• Ultrasound guidance was standard.
• Most clinics encouraged being mobile after transfer.

Lab practices

PGT-A:

• A couple recommended PGT-A for women <35, about half for women 35-37, and most for women >38.
• PGT-A use was variable, 5 clinics would perform it <50% of the time with 7 clinics doing it >50% of the time.

Mosaic/aneuploid embryos:

• Nine of the clinics would transfer mosaic embryos
• Three clinics would transfer aneuploid embryos.

ICSI:

• Four clinics performed ICSI on all patients, and 3 clinics only performed it with male factor.
• Two clinics used PICSI.

Assisted hatching:

• Most clinics used assisted hatching for thawed embryos, while some used it for PGT-A or for thick zonas.

Embryo freezing and thawing:

• There was no consensus on minimum quality for freezing.
• Ten clinics collapsed embryos before freezing.
• Re-expansion of the thawed embryo varied between 2-5 hours.

Air quality:

• All labs used HEPA filtration and positive air pressure.
• Some used volatile organic compound (VOC) filtration.

Culturing equipment:

• About half used isolettes for egg retrievals.
• Nearly all off-gassed plasticware prior to use (this is to remove VOCs).
• All used heated microscope stages, laminar flow hoods, and filtered their gases.
• All labs used a mixed gas of oxygen, nitrogen and carbon dioxide for embryo culture.
• No consensus on what culture media was used.
• Two labs used time-lapse.

Performance indicators:

• Conventional IVF and ICSI fertilization rates
• Oocyte degeneration (death) after ICSI
• Day 5 or day 6 embryo quality
• Clinical pregnancy rates.
• No-result for PGT-A was tracked to the embryologist who performed the biopsy and loaded the sample.

Conclusions

So what are the most common practices among high-performing IVF clinics?

• Combination of LH and FSH during stim
• Intramuscular progesterone for FETs
• Ultrasound-guided embryo transfer
• Freezing blastocysts
• Positive air pressure and HEPA filtration in labs
• Working with heated microscope stages
• Culturing embryos under low oxygen

Besides PGT-A, clinics were generally not consistent with their use of IVF add-ons, such as ERA, PICSI, and timelapse. This is likely due to the lack of clear evidence that these actually work.

There were some issues with the study, mainly that there could have been bias since only one or two physicians actually filled out the survey from each clinic. In addition, since this was a survey with specified questions, there could have been practices that weren’t captured. The results of the survey weren’t validated either, so it’s possible that some responses were exaggerated or in some way weren’t truthful.

Reference

Knudtson JF, Robinson RD, Sparks AE, Hill MJ, Chang TA, Van Voorhis BJ. Common practices among consistently high-performing in vitro fertilization programs in the United States: 10-year update. Fertil Steril. 2022 Jan;117(1):42-50. doi: 10.1016/j.fertnstert.2021.09.010. Epub 2021 Oct 18. PMID: 34674830; PMCID: PMC8714682.

If you liked this post and want to support what I do, please consider a paid subscription, Patreon or donate through PayPal!

 

---

About Embryoman

Embryoman (Sean Lauber) is a former embryologist and the founder of Remembryo, an IVF research and fertility education website. After working in an IVF lab in the US, he returned to Canada and now focuses on making fertility research more accessible. He holds a Master’s in Immunology and launched Remembryo in 2018 to help patients and professionals make sense of IVF research. Sean shares weekly study updates on Facebook, Instagram, and Reddit regularly. He also answers questions on Reddit or in his private Facebook group.

---