It is important to monitor the use of ART and PGT cycles globally. Since the first two world data reports [
1,
2], the ESHRE PGD Consortium has been reporting annual data but the latest report for data I–XV (1997–2013) only contains a total of 56,093 PGT cycles, which includes 32,832 PGT-A, 14,340 PGT-M, and 8921 PGT-SR [
4] and data from just two US clinics. In this report, we have determined that in just 4 years 152,196 primary and 33,170 subsequent cycles of PGT have been carried out in the USA. With the caveat that there are limitations to analysing large data sets, as discussed below, the data presented here reports some key trends for the use of PGT in the USA.
A previous report covering cycles from 2014 to 2016 showed a much higher percentage of PGT in the USA (24%) compared to that in the UK (< 1%) and the possible reasons for this were explored [
6]. Here, we report a continued increase in the use of PGT in the USA. From 2014 through to 2017, the number of PGT cycles significantly increased, reaching an all-time high of 32% of ART cycles in 2017.
In this study, PGT is 5 times more likely to be undertaken in women under the age of 35 years which is in agreement with a previous study [
6]. There could be several reasons for this, including that younger women produce more embryos and so may fit the criteria for PGT and that PGT is often offered after a failed cycle. Older women may be less likely to embark on further IVF after a failed cycle. Several RCTs have been performed on women of advanced maternal age [
12] as they are at most risk of having chromosome abnormalities in their embryos, but studies on younger women have been conducted [
13,
14]. RCTs on PGT-A to date have failed to identify the patients best suited for PGT-A treatment. Further studies are urgently needed to determine which age groups might benefit.
Live birth rates
A limitation of the analysis of the data we present is that it does not adequately control for confounders. A recent study found that ART adjuncts are likely contributing to a decline in ART LBRs [
15]. This is also in line with the statement by the American Society for Reproductive Medicine and the Society for Assisted Reproductive Technology, which advises that PGT-A does not improve ART outcomes [
16]. Further in-depth analyses are required to understand these data further.
It has been suggested that PGT-A will reduce the time to pregnancy, decrease miscarriage rates, and decrease the cost of ART as less ART cycles will be needed. The ESTEEM study showed that PGT-A patients had fewer transfers, fewer miscarriages, and fewer cryopreserved embryos but the same LBR as the control group [
17]. The STAR trial showed no overall improvement in ongoing pregnancy rates at 20 weeks. Subgroup analysis of the women aged 35–40 years did show an increase in ongoing pregnancy rate if two or more embryos were biopsied, but these data were not significant when analysed by intention-to-treat and there was no effect on miscarriage rates [
18]. Studies have shown that PGT cycles result in a lower number of frozen embryos, which will result in a lower cumulative live birth rate [
17‐
19]. For both the ESTEEM and STAR trials, the additional births from frozen embryos have not yet been considered and may result in a lower live birth rate in the PGT-A group as less embryos are frozen after PGT. Only the ESTEEM study on polar body biopsy has shown an effect on miscarriages [
17]; the STAR trial did not [
18].
LBRs are influenced by the denominator used. Clearly, if calculated by the number of cycles started, this will be lower than when calculated by the number of oocyte retrievals which, in turn, will be even lower than when the denominator is the number of embryo transfers. For both PGT and non-PGT, the LBR per embryo transfer is higher than the LBR for oocyte retrieval (Fig.
2). This is because the LBR per transfer only comes into effect if there is a transfer procedure whereas LBR per retrieval and cycle started has to take into account, respectively, cancelled cycles and those with no embryos to transfer.
Subsequent cycles
The number of subsequent PGT cycles increased significantly from 2014 to 2017, with the greatest increase occurring from 2016 to 2017. This increase is unsurprising because many women undergo numerous stimulation cycles to bank embryos that can be used for PGT, which has been shown to increase the chances of having an embryo transfer.
Subsequent cycles are an embryo transfer, from thawed oocytes or embryos, that occurred 1 year or more after the oocyte retrieval or if this was not the first embryo to be transferred. The increase in the number of subsequent PGT cycles could also be explained by the large number of clinics that perform ‘freeze all’ or ‘embryo banking’ cycles, where all oocytes or embryos that result from the initial oocyte retrieval are immediately frozen for later use [
20,
21]. Some studies have shown that transferring a thawed embryo results in a significantly higher live birth rate [
11,
22,
23] but a recent multicentre randomised controlled trial has shown no benefit [
24]. Some clinics may offer to freeze all cycles in association with non-PGT and PGT.
Perhaps the most significant result shown in this study is that the LBR by age for subsequent cycles by PGT showed no evidence of an association between age and LBR, especially for the data for 2017. In the Theobald study, the same result was seen for the HFEA data but not the SART data when considering years 2014–2016. This finding agrees with the hypothesis that PGT-A is used to balance out LBRs across age groups [
25].
PGT use by state—CDC
The CDC data from 2016 and 2017 include 48 reporting states, including US territory Puerto Rico and the District of Columbia (Washington, D.C.). In both 2016 and 2017, there were no clinics in New Hampshire that reported data. Alaska does not have any fertility clinics. Analysis of the data showed that more clinics were using more PGT, giving a significant overall increase in PGT use from 2016 to 2017.
Cost plays a large role in the accessibility of PGT, which makes it important to understand the extent to which PGT is covered by insurance. Despite infertility being registered as a disease by the World Health Organization in 2009, most insurance plans fail to recognize it in their policies [
26].
When assessing PGT use by state, New Mexico, Delaware, Mississippi, California, and Oregon were found to have the highest average PGT use in both 2016 and 2017 (Supplemental Table
1). Interestingly, both Delaware and California, amongst other states, have passed state laws that require insurance companies to cover infertility treatment. The California state law declares that insurers must cover treatment for infertility, indiscriminate of age, gender, marital status, etc. However, the law excludes coverage for ART treatment, and therefore PGT [
27]. This means that the high number of PGT treatments that California performs is self-funded. Delaware’s state law, which was introduced in 2018, is more extensive and includes ART and gamete cryopreservation. This law includes a variety of ART add-ons, including PGT, which may explain why it has the second-highest PGT use of all reporting states in 2016 and 2017 [
27].
In contrast, New Mexico and Oregon do not have state laws that require insurance companies to cover the cost of infertility treatments, which means that, like California, the high percentage of PGT cycles is self-funded.
Four of the states with the lowest average percentage of PGT use were also recurring between 2016 and 2017. The states that were consistently in the bottom include Puerto Rico, West Virginia, Arkansas, and Vermont (Supplementary Table
1C). West Virginia and Arkansas are both governed by laws that require coverage for infertility services. The law in Arkansas includes a lifetime maximum of $15,000, including for the use of ART. The law allows individual insurers to decide which treatments they cover. Therefore, the coverage of PGT varies. It is likely that PGT is not frequently covered by insurance, due to the low percentage of cycles that use PGT in the state of Arkansas. Similarly, West Virginia state law requires infertility services to be covered, but does not define the extent to which they must be covered. Therefore, it is likely that PGT is not covered by insurance, leading to the low percentage of cycles that use PGT in West Virginia [
27]. Neither Puerto Rico nor Vermont has laws that require insurers to cover the costs of infertility services.
Of the states that showed dramatic increases in the percentage of cycles that used PGT, the only state that legally requires coverage is Hawaii. However, the law was last amended in 2003, so it would not have caused a difference between 2016 and 2017. Of the states with the smallest increase, or decrease, in the percentage of cycles that used PGT, Rhode Island, Maryland, and Louisiana all have laws that require the coverage of infertility services. However, all laws were put into place before 2016 and are unlikely to have affected change between 2016 and 2017 [
27].
Partly due to the liberal approach to PGT, the USA has become a popular destination for reproductive tourism, in which people travel to the USA to receive treatments that are not available in their home countries. In 2013, PGT was reported in 19.1% of non-US resident cycles versus 5.3% of US resident cycles [
28]. This likely affects the calculations of PGT use in clinics. This is also likely to contribute to the increased percentage of PGT use in the USA.